Copy byte-aligned NVN streams into aligned submission-owned storage.
Use CPU snapshots only when host visibility is proven safe; otherwise
encode ordered GPU copies before regular, feedback and geometry draws.
Invalidate copies after overlapping writes and pool remaps while keeping
them reusable across unrelated uniform updates. Restore the encoder after
deferred replay when a stream copy split the pass.
Extend t_vbuf to cover all nonzero address residues, copy reuse, queued
copies, deferred updates, fills, shader writes, previous submissions and
pool replacement. Record the general mechanism and Arkham Knight finding.
The per-stream copy limit remains 64 MiB.
Validated on Apple M4 Pro: 84 GPU checks in each of normal, cache-disabled
and encoder-thread modes with Metal validation; full graphics and host
suites; 70 graphics Python tests; 298 tool tests; documentation tests;
iOS compile check (178 files). Full cross-game validation is incomplete:
the harness reported unsupported OpenGL chain checking and its first NVN
shader rebuild did not finish alongside other active builds. No local
Arkham Knight gameplay run.
Co-authored-by: v0lumehi <aljic.zijad@gmail.com>
